Let's divide 625421 by 81
The aim is to understand the frequency of 81 in 625421.

Going ahead to step 1:
81 goes into 6 0 times with a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Subtract 0 from 6 to get 6.
Fetch the next digit (2) from the dividend, attach it to 6 and continue: 62 / 81

Let's proceed to step 2:
81 can be fit into 62 0 times, resulting in a remainder of 62.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 62, we get 62.
Fetch the next digit (5) from the dividend, attach it to 62 and continue: 625 / 81

Advancing to step 3:
81 can be fit into 625 7 times, resulting in a remainder of 58.
Write down 7 as next digit of the result. 
Result so far: 7.0
The remainder is 58 after subtracting 567 from 625.
Bring next digit (4) of the dividend behind the 58 and repeat the process: 584 / 81

Step 4:
When dividing 584 by 81, we get 7 with a remainder of 17.
The next digit of our result is 7. 
Result so far: 77.0
The remainder is 17 after subtracting 567 from 584.
Fetch the next digit (2) from the dividend, attach it to 17 and continue: 172 / 81

Going ahead to step 5:
172 divided by 81 is 2 with a remainder of 10.
Put 2 as the next digit of the answer. 
Result so far: 772.0
Subtract 162 from 172 to get 10.
Include the next digit (1) from the dividend after 10, then repeat: 101 / 81

Going ahead to step 6:
When dividing 101 by 81, we get 1 with a remainder of 20.
Write down 1 as next digit of the result. 
Result so far: 7721.0
Subtract 81 from 101 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Going ahead to step 7:
When dividing 200 by 81, we get 2 with a remainder of 38.
Put 2 as the next digit of the answer. 
Result so far: 7721.2
Subtract 162 from 200 to get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Step 8:
380 divided by 81 is 4 with a remainder of 56.
Use 4 as the next digit of our solution. 
Result so far: 7721.24
The remainder is 56 after subtracting 324 from 380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 560, and continue the process.

Advancing to step 9:
When dividing 560 by 81, we get 6 with a remainder of 74.
Use 6 as the next digit of our solution. 
Result so far: 7721.246
Deduct 486 from 560 and we're left with 74.
Since there are no more digits in the dividend, we add a zero to the remainder making it 740, and continue the process.

Advancing to step 10:
740 divided by 81 is 9 with a remainder of 11.
The number 9 becomes the next digit in our result. 
Result so far: 7721.2469
Subtract 729 from 740 to get 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

Going ahead to step 11:
81 goes into 110 1 times with a remainder of 29.
Put 1 as the next digit of the answer. 
Result so far: 7721.24691
Subtracting 81 from 110 leaves us with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Step 12:
81 goes into 290 3 times with a remainder of 47.
Put 3 as the next digit of the answer. 
Result so far: 7721.246913
The remainder is 47 after subtracting 243 from 290.
Since there are no more digits in the dividend, we add a zero to the remainder making it 470, and continue the process.

Let's proceed to step 13:
81 goes into 470 5 times with a remainder of 65.
Write down 5 as next digit of the result. 
Result so far: 7721.2469135
The remainder is 65 after subtracting 405 from 470.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Let's proceed to step 14:
When dividing 650 by 81, we get 8 with a remainder of 2.
The number 8 becomes the next digit in our result. 
Result so far: 7721.24691358
Subtract 648 from 650 to get 2.
Since there are no more digits in the dividend, we add a zero to the remainder making it 20, and continue the process.

After the division, we end up with 7721.24691358 and a remainder of 2e-09.